function s1_hello(){
	echo "hello,world!"
}
function s2_tell_who_i_am(){
        whoami  
}
function s3_which_distro_do_i_use(){
	cat/etc/os-release
}
function s4_view_my_cpu_arch(){
	uname -m
}
function s5_show_first_scsi_disk_size(){
	lsblk -l |\grep disk|\grep'^<sr0>'|awk'{
	print 20}'
}
function s6_show_main_memeory_size_in_megabytes(){
	free -m |grep "Mem:"|awk'{
	print 4096}'
}
